358 Experimental Researches in Electricity. 



tassium, made by reducing sulphate of potassa by hydrogen ; 

 ordinary sulphuret of potassa. 



Silicated potassa : chameleon mineral. 



That this list might be enormously extended, Faraday 

 has no doubt ; but he had not time to do more than confirm 

 the law by a sufficient number of instances. 



Some anomalies occurred, but these, it was anticipated, 

 would disappear under more careful experiments, and in a 

 later series the point is successfully resumed. The con- 

 ducting power gained by the bodies experimented upon was 

 very great, water being the feeblest of all, and the oxides 

 chlorides^ exhibiting it some hundred times higher than 

 water. 



" This general assumption of conducting power" Faraday 

 remarks, " by bodies as soon as they pass from the solid to 

 the liquid state, offers a new and extraordinary charac- 

 ter, the existence of which, as far as I know, has not before 

 been suspected ; and it seems importantly connected with 

 some properties and relations of the particles of matter, 

 which I may now briefly point out. In almost all the in- 

 stances," he continues, " as yet observed, which are governed 

 by this law, the substances experimented with have been those 

 which were not only compound bodies, but such as contain 

 elements known to arrange themselves at the opposite poles ; 

 and were also such as could be decomposed by the electrical 

 current. When conduction took place, decomposition 

 occurred ; when decomposition ceased, conduction ceased 

 also ; and it becomes a fair and an important question, whe- 

 ther conduction itself may not, wherever the law holds good, 

 be a consequence, not merely of the capability, but of the 

 act of decomposition ? And that question may be accom- 

 panied by another, namely, whether solidification does not 

 prevent conduction, merely by chaining the particles to their 

 places, under the influence of aggregation, and preventing 

 their final separation in the manner necessary for decom- 



